From patchwork Sun Nov 17 00:22:34 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Eric Biggers X-Patchwork-Id: 13877766 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 54E08D68BF6 for ; Sun, 17 Nov 2024 00:25:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=btP8mqVP5G/X80JPe+S3kaiHzWm+BDiIv6+qLQbcw54=; b=u7zoXweVCZR+0/MkNT7GhapUyz /ch1SUM7ZmU2O+bWlGDT/gVh1zNDE2xbpsd1NLsZrjeLcJSSn+CV+aOXQm7IB4WiEOm6hJ/t7ok6c JJOZ7KhXsJkQMFwPwrPT5gxvPfO6nCY2UYZeTl05IFTn2E+e4hj0kV3OGn3KWzDmHjCqJPlEhTn8I xEf2CnA6mxEBDFz2M450ZfEzw22NFsMWnvYIa/E6F9lVEzLLJHY459rM63c9xmVaTi3iiXrJDdxvt o2+ueoPWBprSp+3RwWxHrWtiem3NKdixTNzws+sJiS/xCPKkS8xXMJG8io/ztA6KrVG1RclF3ywMj oRv25DKQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tCT5z-00000006aLS-1xuk; Sun, 17 Nov 2024 00:24:55 +0000 Received: from nyc.source.kernel.org ([2604:1380:45d1:ec00::3]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tCT51-00000006Zqz-3XCX for linux-arm-kernel@lists.infradead.org; Sun, 17 Nov 2024 00:23:57 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id 90A4EA40BEE; Sun, 17 Nov 2024 00:22:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BBBDEC4CED2; Sun, 17 Nov 2024 00:23:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1731803034; bh=CGWQhKW6ZnmQfEVvqvVPnQBpPTN+czhYXoOYIavQbgs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nhgzJPj7UB/alJuoFhQJmwXTMxqt2eknRRtihGE/xoxv2b/JH2zQE8dmAU13HCmGS dHRai3+caX8aDZZYf76elLUQaAvsj4pIqA3r4c1rdaE3oY4DJcoLm5CZEF/7zJCyF6 5cHb0Axa5Px1IXxjLOK+xmjtN7mgLDW0Lrj2KuWCdzuUGZb9sCie0CVu2bM+/YPEPI cuZ8cs6Nxs4hsYqOm114xzK7KxH3Spbbdt1HXLerQX5S+1nEoMNQIt6EwnWtM6oJGs zGKyhA+ezxhensu8Ym4OW/JSQ1prRxqvsC/l0m+8CUPN2O5UTe067T1bact+o1wav9 fKkqmFy8ZShNA== From: Eric Biggers To: linux-kernel@vger.kernel.org Cc: linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-crypto@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, x86@kernel.org, Zhihang Shao , Ard Biesheuvel Subject: [PATCH 01/11] lib/crc-t10dif: stop wrapping the crypto API Date: Sat, 16 Nov 2024 16:22:34 -0800 Message-ID: <20241117002244.105200-2-ebiggers@kernel.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241117002244.105200-1-ebiggers@kernel.org> References: <20241117002244.105200-1-ebiggers@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241116_162356_016903_5E00AC2C X-CRM114-Status: GOOD ( 26.03 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Eric Biggers In preparation for making the CRC-T10DIF library optimized for each architecture, like what has been done for CRC32, get rid of the weird layering where crc_t10dif_update() calls into the crypto API. Instead, move crc_t10dif_generic() into the crc-t10dif library module, and make crc_t10dif_update() just call crc_t10dif_generic(). Acceleration will be reintroduced via crc_t10dif_arch() in the following patches. Signed-off-by: Eric Biggers --- crypto/Kconfig | 1 + crypto/Makefile | 2 +- crypto/crct10dif_common.c | 82 ------------------- include/linux/crc-t10dif.h | 16 ++-- lib/Kconfig | 2 - lib/crc-t10dif.c | 156 +++++++++++-------------------------- 6 files changed, 58 insertions(+), 201 deletions(-) delete mode 100644 crypto/crct10dif_common.c diff --git a/crypto/Kconfig b/crypto/Kconfig index a779cab668c2..b3bf7800dd94 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -1099,10 +1099,11 @@ config CRYPTO_CRC32 Used by RoCEv2 and f2fs. config CRYPTO_CRCT10DIF tristate "CRCT10DIF" select CRYPTO_HASH + select CRC_T10DIF help CRC16 CRC algorithm used for the T10 (SCSI) Data Integrity Field (DIF) CRC algorithm used by the SCSI Block Commands standard. diff --git a/crypto/Makefile b/crypto/Makefile index a1ce3fa5298d..e948a883f151 100644 --- a/crypto/Makefile +++ b/crypto/Makefile @@ -152,11 +152,11 @@ obj-$(CONFIG_CRYPTO_DEFLATE) += deflate.o obj-$(CONFIG_CRYPTO_MICHAEL_MIC) += michael_mic.o obj-$(CONFIG_CRYPTO_CRC32C) += crc32c_generic.o obj-$(CONFIG_CRYPTO_CRC32) += crc32_generic.o CFLAGS_crc32c_generic.o += -DARCH=$(ARCH) CFLAGS_crc32_generic.o += -DARCH=$(ARCH) -obj-$(CONFIG_CRYPTO_CRCT10DIF) += crct10dif_common.o crct10dif_generic.o +obj-$(CONFIG_CRYPTO_CRCT10DIF) += crct10dif_generic.o obj-$(CONFIG_CRYPTO_CRC64_ROCKSOFT) += crc64_rocksoft_generic.o obj-$(CONFIG_CRYPTO_AUTHENC) += authenc.o authencesn.o obj-$(CONFIG_CRYPTO_LZO) += lzo.o lzo-rle.o obj-$(CONFIG_CRYPTO_LZ4) += lz4.o obj-$(CONFIG_CRYPTO_LZ4HC) += lz4hc.o diff --git a/crypto/crct10dif_common.c b/crypto/crct10dif_common.c deleted file mode 100644 index b2fab366f518..000000000000 --- a/crypto/crct10dif_common.c +++ /dev/null @@ -1,82 +0,0 @@ -/* - * Cryptographic API. - * - * T10 Data Integrity Field CRC16 Crypto Transform - * - * Copyright (c) 2007 Oracle Corporation. All rights reserved. - * Written by Martin K. Petersen - * Copyright (C) 2013 Intel Corporation - * Author: Tim Chen - * - * This program is free software; you can redistribute it and/or modify it - * under the terms of the GNU General Public License as published by the Free - * Software Foundation; either version 2 of the License, or (at your option) - * any later version. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, - * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF - * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND - * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS - * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN - * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN - * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE - * SOFTWARE. - * - */ - -#include -#include -#include - -/* Table generated using the following polynomium: - * x^16 + x^15 + x^11 + x^9 + x^8 + x^7 + x^5 + x^4 + x^2 + x + 1 - * gt: 0x8bb7 - */ -static const __u16 t10_dif_crc_table[256] = { - 0x0000, 0x8BB7, 0x9CD9, 0x176E, 0xB205, 0x39B2, 0x2EDC, 0xA56B, - 0xEFBD, 0x640A, 0x7364, 0xF8D3, 0x5DB8, 0xD60F, 0xC161, 0x4AD6, - 0x54CD, 0xDF7A, 0xC814, 0x43A3, 0xE6C8, 0x6D7F, 0x7A11, 0xF1A6, - 0xBB70, 0x30C7, 0x27A9, 0xAC1E, 0x0975, 0x82C2, 0x95AC, 0x1E1B, - 0xA99A, 0x222D, 0x3543, 0xBEF4, 0x1B9F, 0x9028, 0x8746, 0x0CF1, - 0x4627, 0xCD90, 0xDAFE, 0x5149, 0xF422, 0x7F95, 0x68FB, 0xE34C, - 0xFD57, 0x76E0, 0x618E, 0xEA39, 0x4F52, 0xC4E5, 0xD38B, 0x583C, - 0x12EA, 0x995D, 0x8E33, 0x0584, 0xA0EF, 0x2B58, 0x3C36, 0xB781, - 0xD883, 0x5334, 0x445A, 0xCFED, 0x6A86, 0xE131, 0xF65F, 0x7DE8, - 0x373E, 0xBC89, 0xABE7, 0x2050, 0x853B, 0x0E8C, 0x19E2, 0x9255, - 0x8C4E, 0x07F9, 0x1097, 0x9B20, 0x3E4B, 0xB5FC, 0xA292, 0x2925, - 0x63F3, 0xE844, 0xFF2A, 0x749D, 0xD1F6, 0x5A41, 0x4D2F, 0xC698, - 0x7119, 0xFAAE, 0xEDC0, 0x6677, 0xC31C, 0x48AB, 0x5FC5, 0xD472, - 0x9EA4, 0x1513, 0x027D, 0x89CA, 0x2CA1, 0xA716, 0xB078, 0x3BCF, - 0x25D4, 0xAE63, 0xB90D, 0x32BA, 0x97D1, 0x1C66, 0x0B08, 0x80BF, - 0xCA69, 0x41DE, 0x56B0, 0xDD07, 0x786C, 0xF3DB, 0xE4B5, 0x6F02, - 0x3AB1, 0xB106, 0xA668, 0x2DDF, 0x88B4, 0x0303, 0x146D, 0x9FDA, - 0xD50C, 0x5EBB, 0x49D5, 0xC262, 0x6709, 0xECBE, 0xFBD0, 0x7067, - 0x6E7C, 0xE5CB, 0xF2A5, 0x7912, 0xDC79, 0x57CE, 0x40A0, 0xCB17, - 0x81C1, 0x0A76, 0x1D18, 0x96AF, 0x33C4, 0xB873, 0xAF1D, 0x24AA, - 0x932B, 0x189C, 0x0FF2, 0x8445, 0x212E, 0xAA99, 0xBDF7, 0x3640, - 0x7C96, 0xF721, 0xE04F, 0x6BF8, 0xCE93, 0x4524, 0x524A, 0xD9FD, - 0xC7E6, 0x4C51, 0x5B3F, 0xD088, 0x75E3, 0xFE54, 0xE93A, 0x628D, - 0x285B, 0xA3EC, 0xB482, 0x3F35, 0x9A5E, 0x11E9, 0x0687, 0x8D30, - 0xE232, 0x6985, 0x7EEB, 0xF55C, 0x5037, 0xDB80, 0xCCEE, 0x4759, - 0x0D8F, 0x8638, 0x9156, 0x1AE1, 0xBF8A, 0x343D, 0x2353, 0xA8E4, - 0xB6FF, 0x3D48, 0x2A26, 0xA191, 0x04FA, 0x8F4D, 0x9823, 0x1394, - 0x5942, 0xD2F5, 0xC59B, 0x4E2C, 0xEB47, 0x60F0, 0x779E, 0xFC29, - 0x4BA8, 0xC01F, 0xD771, 0x5CC6, 0xF9AD, 0x721A, 0x6574, 0xEEC3, - 0xA415, 0x2FA2, 0x38CC, 0xB37B, 0x1610, 0x9DA7, 0x8AC9, 0x017E, - 0x1F65, 0x94D2, 0x83BC, 0x080B, 0xAD60, 0x26D7, 0x31B9, 0xBA0E, - 0xF0D8, 0x7B6F, 0x6C01, 0xE7B6, 0x42DD, 0xC96A, 0xDE04, 0x55B3 -}; - -__u16 crc_t10dif_generic(__u16 crc, const unsigned char *buffer, size_t len) -{ - unsigned int i; - - for (i = 0 ; i < len ; i++) - crc = (crc << 8) ^ t10_dif_crc_table[((crc >> 8) ^ buffer[i]) & 0xff]; - - return crc; -} -EXPORT_SYMBOL(crc_t10dif_generic); - -MODULE_DESCRIPTION("T10 DIF CRC calculation common code"); -MODULE_LICENSE("GPL"); diff --git a/include/linux/crc-t10dif.h b/include/linux/crc-t10dif.h index 6bb0c0bf357b..206ba2305483 100644 --- a/include/linux/crc-t10dif.h +++ b/include/linux/crc-t10dif.h @@ -4,13 +4,19 @@ #include #define CRC_T10DIF_DIGEST_SIZE 2 #define CRC_T10DIF_BLOCK_SIZE 1 -#define CRC_T10DIF_STRING "crct10dif" -extern __u16 crc_t10dif_generic(__u16 crc, const unsigned char *buffer, - size_t len); -extern __u16 crc_t10dif(unsigned char const *, size_t); -extern __u16 crc_t10dif_update(__u16 crc, unsigned char const *, size_t); +u16 crc_t10dif_generic(u16 crc, const u8 *p, size_t len); + +static inline u16 crc_t10dif_update(u16 crc, const u8 *p, size_t len) +{ + return crc_t10dif_generic(crc, p, len); +} + +static inline u16 crc_t10dif(const u8 *p, size_t len) +{ + return crc_t10dif_update(0, p, len); +} #endif diff --git a/lib/Kconfig b/lib/Kconfig index b894ee64ff95..eb6c7a023be9 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -142,12 +142,10 @@ config CRC16 the kernel tree does. Such modules that use library CRC16 functions require M here. config CRC_T10DIF tristate "CRC calculation for the T10 Data Integrity Field" - select CRYPTO - select CRYPTO_CRCT10DIF help This option is only needed if a module that's not in the kernel tree needs to calculate CRC checks for use with the SCSI data integrity subsystem. diff --git a/lib/crc-t10dif.c b/lib/crc-t10dif.c index 1ed2ed487097..311c2ab829f1 100644 --- a/lib/crc-t10dif.c +++ b/lib/crc-t10dif.c @@ -7,125 +7,59 @@ */ #include #include #include -#include -#include -#include -#include -#include -#include -static struct crypto_shash __rcu *crct10dif_tfm; -static DEFINE_STATIC_KEY_TRUE(crct10dif_fallback); -static DEFINE_MUTEX(crc_t10dif_mutex); -static struct work_struct crct10dif_rehash_work; - -static int crc_t10dif_notify(struct notifier_block *self, unsigned long val, void *data) -{ - struct crypto_alg *alg = data; - - if (val != CRYPTO_MSG_ALG_LOADED || - strcmp(alg->cra_name, CRC_T10DIF_STRING)) - return NOTIFY_DONE; - - schedule_work(&crct10dif_rehash_work); - return NOTIFY_OK; -} - -static void crc_t10dif_rehash(struct work_struct *work) -{ - struct crypto_shash *new, *old; - - mutex_lock(&crc_t10dif_mutex); - old = rcu_dereference_protected(crct10dif_tfm, - lockdep_is_held(&crc_t10dif_mutex)); - new = crypto_alloc_shash(CRC_T10DIF_STRING, 0, 0); - if (IS_ERR(new)) { - mutex_unlock(&crc_t10dif_mutex); - return; - } - rcu_assign_pointer(crct10dif_tfm, new); - mutex_unlock(&crc_t10dif_mutex); - - if (old) { - synchronize_rcu(); - crypto_free_shash(old); - } else { - static_branch_disable(&crct10dif_fallback); - } -} - -static struct notifier_block crc_t10dif_nb = { - .notifier_call = crc_t10dif_notify, +/* + * Table generated using the following polynomial: + * x^16 + x^15 + x^11 + x^9 + x^8 + x^7 + x^5 + x^4 + x^2 + x + 1 + * gt: 0x8bb7 + */ +static const u16 t10_dif_crc_table[256] = { + 0x0000, 0x8BB7, 0x9CD9, 0x176E, 0xB205, 0x39B2, 0x2EDC, 0xA56B, + 0xEFBD, 0x640A, 0x7364, 0xF8D3, 0x5DB8, 0xD60F, 0xC161, 0x4AD6, + 0x54CD, 0xDF7A, 0xC814, 0x43A3, 0xE6C8, 0x6D7F, 0x7A11, 0xF1A6, + 0xBB70, 0x30C7, 0x27A9, 0xAC1E, 0x0975, 0x82C2, 0x95AC, 0x1E1B, + 0xA99A, 0x222D, 0x3543, 0xBEF4, 0x1B9F, 0x9028, 0x8746, 0x0CF1, + 0x4627, 0xCD90, 0xDAFE, 0x5149, 0xF422, 0x7F95, 0x68FB, 0xE34C, + 0xFD57, 0x76E0, 0x618E, 0xEA39, 0x4F52, 0xC4E5, 0xD38B, 0x583C, + 0x12EA, 0x995D, 0x8E33, 0x0584, 0xA0EF, 0x2B58, 0x3C36, 0xB781, + 0xD883, 0x5334, 0x445A, 0xCFED, 0x6A86, 0xE131, 0xF65F, 0x7DE8, + 0x373E, 0xBC89, 0xABE7, 0x2050, 0x853B, 0x0E8C, 0x19E2, 0x9255, + 0x8C4E, 0x07F9, 0x1097, 0x9B20, 0x3E4B, 0xB5FC, 0xA292, 0x2925, + 0x63F3, 0xE844, 0xFF2A, 0x749D, 0xD1F6, 0x5A41, 0x4D2F, 0xC698, + 0x7119, 0xFAAE, 0xEDC0, 0x6677, 0xC31C, 0x48AB, 0x5FC5, 0xD472, + 0x9EA4, 0x1513, 0x027D, 0x89CA, 0x2CA1, 0xA716, 0xB078, 0x3BCF, + 0x25D4, 0xAE63, 0xB90D, 0x32BA, 0x97D1, 0x1C66, 0x0B08, 0x80BF, + 0xCA69, 0x41DE, 0x56B0, 0xDD07, 0x786C, 0xF3DB, 0xE4B5, 0x6F02, + 0x3AB1, 0xB106, 0xA668, 0x2DDF, 0x88B4, 0x0303, 0x146D, 0x9FDA, + 0xD50C, 0x5EBB, 0x49D5, 0xC262, 0x6709, 0xECBE, 0xFBD0, 0x7067, + 0x6E7C, 0xE5CB, 0xF2A5, 0x7912, 0xDC79, 0x57CE, 0x40A0, 0xCB17, + 0x81C1, 0x0A76, 0x1D18, 0x96AF, 0x33C4, 0xB873, 0xAF1D, 0x24AA, + 0x932B, 0x189C, 0x0FF2, 0x8445, 0x212E, 0xAA99, 0xBDF7, 0x3640, + 0x7C96, 0xF721, 0xE04F, 0x6BF8, 0xCE93, 0x4524, 0x524A, 0xD9FD, + 0xC7E6, 0x4C51, 0x5B3F, 0xD088, 0x75E3, 0xFE54, 0xE93A, 0x628D, + 0x285B, 0xA3EC, 0xB482, 0x3F35, 0x9A5E, 0x11E9, 0x0687, 0x8D30, + 0xE232, 0x6985, 0x7EEB, 0xF55C, 0x5037, 0xDB80, 0xCCEE, 0x4759, + 0x0D8F, 0x8638, 0x9156, 0x1AE1, 0xBF8A, 0x343D, 0x2353, 0xA8E4, + 0xB6FF, 0x3D48, 0x2A26, 0xA191, 0x04FA, 0x8F4D, 0x9823, 0x1394, + 0x5942, 0xD2F5, 0xC59B, 0x4E2C, 0xEB47, 0x60F0, 0x779E, 0xFC29, + 0x4BA8, 0xC01F, 0xD771, 0x5CC6, 0xF9AD, 0x721A, 0x6574, 0xEEC3, + 0xA415, 0x2FA2, 0x38CC, 0xB37B, 0x1610, 0x9DA7, 0x8AC9, 0x017E, + 0x1F65, 0x94D2, 0x83BC, 0x080B, 0xAD60, 0x26D7, 0x31B9, 0xBA0E, + 0xF0D8, 0x7B6F, 0x6C01, 0xE7B6, 0x42DD, 0xC96A, 0xDE04, 0x55B3 }; -__u16 crc_t10dif_update(__u16 crc, const unsigned char *buffer, size_t len) -{ - struct { - struct shash_desc shash; - __u16 crc; - } desc; - int err; - - if (static_branch_unlikely(&crct10dif_fallback)) - return crc_t10dif_generic(crc, buffer, len); - - rcu_read_lock(); - desc.shash.tfm = rcu_dereference(crct10dif_tfm); - desc.crc = crc; - err = crypto_shash_update(&desc.shash, buffer, len); - rcu_read_unlock(); - - BUG_ON(err); - - return desc.crc; -} -EXPORT_SYMBOL(crc_t10dif_update); - -__u16 crc_t10dif(const unsigned char *buffer, size_t len) -{ - return crc_t10dif_update(0, buffer, len); -} -EXPORT_SYMBOL(crc_t10dif); - -static int __init crc_t10dif_mod_init(void) -{ - INIT_WORK(&crct10dif_rehash_work, crc_t10dif_rehash); - crypto_register_notifier(&crc_t10dif_nb); - crc_t10dif_rehash(&crct10dif_rehash_work); - return 0; -} - -static void __exit crc_t10dif_mod_fini(void) -{ - crypto_unregister_notifier(&crc_t10dif_nb); - cancel_work_sync(&crct10dif_rehash_work); - crypto_free_shash(rcu_dereference_protected(crct10dif_tfm, 1)); -} - -module_init(crc_t10dif_mod_init); -module_exit(crc_t10dif_mod_fini); - -static int crc_t10dif_transform_show(char *buffer, const struct kernel_param *kp) +u16 crc_t10dif_generic(u16 crc, const u8 *p, size_t len) { - struct crypto_shash *tfm; - int len; + size_t i; - if (static_branch_unlikely(&crct10dif_fallback)) - return sprintf(buffer, "fallback\n"); + for (i = 0; i < len; i++) + crc = (crc << 8) ^ t10_dif_crc_table[(crc >> 8) ^ p[i]]; - rcu_read_lock(); - tfm = rcu_dereference(crct10dif_tfm); - len = snprintf(buffer, PAGE_SIZE, "%s\n", - crypto_shash_driver_name(tfm)); - rcu_read_unlock(); - - return len; + return crc; } +EXPORT_SYMBOL(crc_t10dif_generic); -module_param_call(transform, NULL, crc_t10dif_transform_show, NULL, 0444); - -MODULE_DESCRIPTION("T10 DIF CRC calculation (library API)"); +MODULE_DESCRIPTION("T10 DIF CRC calculation"); MODULE_LICENSE("GPL"); -MODULE_SOFTDEP("pre: crct10dif");